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View Full Version : 55 Gal barrel of alchemist's fire?



Furnok
2010-07-16, 09:09 AM
I spoke with my DM we are using one assumption 1.) The specific gravity of alchemist fire is equal to the equivalent of Napalm.

There are 23.9445 uses of alchemists fire in a barrel with a total weight of 410.8863 Lbs per barrel (I did the math just trust me).

Edit* Sorry I redid my math its not 23.9445 uses its 410.8863 uses because one unit of AF = 1 pound. To get total wieght of a barrel take 55 (# of gal in the barrel) x 8.322 (total wieght of 1 gal of water) x .8977 (specific gravity of Naplam)

The reason why this came up is in game my character is a king of a country and we just got word an army is marching on the capital. The opposing army built massive troop transport constructs that are immune to magic (my army realizes on magic on the battle field) and that the constructs have fire immunity 10 (roughly). My original idea was to get barrels of alchemist fire and use teleport object so that the barrel would fall right on the construct since alchemist fire is real fire and not magical I was assuming that it would get through the magic resistance. My DM brought up the fire resistance I thought that it wouldn’t be a problem but he said that the barrel is not one attack but 23.9445 separate attacks and that each attack (1D6) wouldn’t get through the fire resistance. Anyways I wanted to see what you guys thought.

I have already moved on since the DM basically said so now I am just going to drop an 1100 Lb boulder on the transports from 100 ft up. It wont do as much damage but it will cost far less.

gbprime
2010-07-16, 09:11 AM
Right. Alchemists Fire does 1d6. If you use a lot of it, it does 1d6 a lot of times. Fire Resistance 10 is still proof against it.

Can you make acid instead?

Failing that, can you use all the magic you supposedly have to change the terrain they're moving over? Some constructs don't deal well with pits and trenches. Or deep mud.

And you could always fill the inside of those transports with summoned swarms...

Aroka
2010-07-16, 09:18 AM
It seems obvious that the damage dealt by fires does not increase linearly. A barrel of alchemist's fire does not deal Xd6 damage (X being the number of flasks poured in), but it also doesn't do X attacks for d6 damage.

Being immersed in lava does, what, 20d6 damage? Regular fire (not magical, not coming out of a dragon, etc.) should never do that much damage. A bigger fire will generally do more damage in D&D, though, and obviously all at once.

A barrel of fire, flaming oil poured from a battlement, etc. should probably deal between 3d6 and 10d6 damage, with Ref DC 15 to halve and avoid catching on fire (one save is enough, really) for another 1d6 per round until extinguished.

Ormagoden
2010-07-16, 09:28 AM
I'd just make it the same as a flask just affecting a much much wider area.
So everything in oh, say, 30ft takes 1d6 fire and needs a reflex save.

Also spike growth at choke points.

Natael
2010-07-16, 09:30 AM
Acid flasks. If you have a bunch of people that can fly, have them drop stuff from really high up onto the enemy, as falling objects can do a fair bit of damage. Conjuration magic gets through magical immunity/resistance usually, with some decent, non-fire choices even in core.

DracoDei
2010-07-16, 09:32 AM
Actually, I encourage this sort of thing in my games, and DO have the damage scale linearly (I have been told that even this doesn't really make it cost effective at higher levels, although factoring in SR might change that). I guess at really high volumes such as this, I might put a maximum on the damage based on the size of the target (basically some vague representation of what it would take to fully cover the side of them the fire is impacting from), or delay some of the damage to a later round as it actually has enough thickness to it that it can't all burn up in 3 to 6 seconds.

I do question your result that a flask of alchemist's fire is over 2 gallons though...

Enguhl
2010-07-16, 09:34 AM
Actually its perfectly possible (if I'm reading the situation correctly), since damage to vehicles is done by 10ft section, so it could take 4d6 damage due to an area being covered in alchemists fire (in one turn).
Obviously acid would be better, but fire still works.

ericgrau
2010-07-16, 09:36 AM
There is 1 alchemist fire per pound or pint and 320 per 40 gallon barrel. I dunno where you got your math.

That said, being on fire or surrounded completely by mundane fire does only 1d6, and total immersion in lava does 20d6. Depending on how you interpret it there either isn't more "on fire" than "on fire" and your foes only take 1d6. Or at worst 20d6. Also from a balance standpoint stacking a million X's is a common form of abuse. I would allow an increase in area of effect instead, perhaps a 5 foot square per flask, circular spread, 1d6 to anyone hit directly or fully surrounded by flame and 1d3 (per alchemist fire rules) to anyone standing in the spreading flames. Or maybe the substance doesn't spread very well and increase the duration at the expense of area.

Btw, immersion in acid is 10d6 per round by RAW. But that would take a lot of acid.

Ravens_cry
2010-07-16, 09:39 AM
It seems obvious that the damage dealt by fires does not increase linearly. A barrel of alchemist's fire does not deal Xd6 damage (X being the number of flasks poured in), but it also doesn't do X attacks for d6 damage.

Being immersed in lava does, what, 20d6 damage? Regular fire (not magical, not coming out of a dragon, etc.) should never do that much damage. A bigger fire will generally do more damage in D&D, though, and obviously all at once.

A barrel of fire, flaming oil poured from a battlement, etc. should probably deal between 3d6 and 10d6 damage, with Ref DC 15 to halve and avoid catching on fire (one save is enough, really) for another 1d6 per round until extinguished.
Ah, but regular fire is a gas, and gases conduct weakly. A barrel of alchemist fire is a burning liquid, and so it would conduct the heat of the flames better. You can wave your hand in a fire and be fine, try doing the same in an on fire deep fryer.

Tyndmyr
2010-07-16, 09:45 AM
Lava does 20d6 for immersion.

So...find a source of lava, and abuse it. Or superheat rock, and make your own.

Aroka
2010-07-16, 09:46 AM
Ah, but regular fire is a gas, and gases conduct weakly. A barrel of alchemist fire is a burning liquid, and so it would conduct the heat of the flames better. You can wave your hand in a fire and be fine, try doing the same in an on fire deep fryer.

That's as may be - I'm not going to take stances on heat conduction or bother looking them up - but it seems my suggestion covers that pretty well: it does more damage and continues to deal damage, since you're covered in an incendiary, rather than being roasted in a fire (1d6 damage/round).

Ravens_cry
2010-07-16, 09:50 AM
That's as may be - I'm not going to take stances on heat conduction or bother looking them up - but it seems my suggestion covers that pretty well: it does more damage and continues to deal damage, since you're covered in an incendiary, rather than being roasted in a fire (1d6 damage/round).
Sorry, I thought 3d6 was your upper limit. 8d6 sounds about right to me.

Aroka
2010-07-16, 10:06 AM
8d6 does sound pretty good; the number is high enough to matter, but probably won't decide things by itself. Increasing the amount of fuel would mostly affect a larger area and (perhaps) for a longer time.

Another_Poet
2010-07-16, 10:14 AM
I would suggest you make acid (http://www.d20srd.org/srd/equipment/goodsandservices.htm#acid) instead. It's cheaper to make and they aren't immune, so it will do more damage despite the lack of ongoing next-round damage.

Aroka
2010-07-16, 10:35 AM
Oh, and whether acid or burning liquid (Greek/alchemist's fire, oil, whatever), since this is a troop transport you're attacking, some should get inside to kill the troops. (I think fire might be better for that, really.) Unless the transport is NBC-sealed or something....

Ravens_cry
2010-07-16, 11:05 AM
Oh, and whether acid or burning liquid (Greek/alchemist's fire, oil, whatever), since this is a troop transport you're attacking, some should get inside to kill the troops. (I think fire might be better for that, really.) Unless the transport is NBC-sealed or something....

Acid bypasses hardness, so it would be great for disabling the transports. This would severelly slow them down and allows you to prepare other defenses.
Aerial bombing of shrunken boulders from above arrow range would probably be a good tactic.

Hurlbut
2010-07-16, 11:12 AM
Eh just get a bunch of barrels full of blackpowder, attach a flask of alchemist's fire inside each. Drop them, sit back and watch the fireworks.

Curmudgeon
2010-07-16, 11:15 AM
I'm concerned with your barrel assumptions. The D&D barrel holds 10 gallons and is made of wood, and would immediately fail if filled with alchemist's fire. A 55 gallon steel oil drum is a 20th Century invention, so that's completely unrealistic. D&D flasks are made of non-burning ceramic. Scaling up one of those so it would support its own weight plus 55 gallons of liquid would make it very heavy: in the hundreds of pounds. (40 gallon oak whisky barrels weigh about 125 lbs., and ceramic is at least 3x as dense as oak.) Plus just making one would normally require novel technology in the form of an extremely large kiln. So what we're really talking about is needing a Fabricate spell plus a Craft check of about DC 15. Then you've got to be able to pour out the barrel, which is going to require a character with at least 24 Strength or some pulley+rope+pivot mechanism. (If you use the leverage multiplier you won't be able to shift where you pour the contents as easily as one person with enough Strength would.)

Seems like a lot of work required for dubious results.

Ravens_cry
2010-07-16, 11:21 AM
Alchimest fire appears to burn when exposed to air.
Wet Coopers (http://www.ehow.com/way_5397339_making-sugar-barrels-colonial-times.html) were able to make airtight, watertight barrels for transporting liquid, even under pressure, like beer.

urbanpirate
2010-07-16, 11:26 AM
just throw tigers:biggrin:

LibraryOgre
2010-07-16, 11:29 AM
Right. Alchemists Fire does 1d6. If you use a lot of it, it does 1d6 a lot of times. Fire Resistance 10 is still proof against it.


I disagree. If he was throwing individual flasks of alchemist fire that many times, yeah, but we're talking a single attack... That's gonna be a lot of fire.

Psyx
2010-07-16, 11:31 AM
I'd personally rule that more of the stuff doesn't burn hotter: There's just more of it.

So at most it would do 1d6 damage.... twenty times (or however much is in the barrel); which isn't going to get through fire resistance. Alternatively it might just burn for longer.

LibraryOgre
2010-07-16, 11:42 AM
I'd personally rule that more of the stuff doesn't burn hotter: There's just more of it.

There's more of it, yes, which means it's doing much more damage.

DaTedinator
2010-07-16, 11:44 AM
Speaking entirely RAW?

RAW, it seems it would do 1d6 damage X times.

However, RAW, that's not a problem for you (http://www.d20srd.org/srd/specialAbilities.htm#resistanceToEnergy):

A creature with resistance to energy has the ability (usually extraordinary) to ignore some damage of a certain type each round, but it does not have total immunity.(Emphasis mine)

Outside of RAW, both of those seem odd to me.

Aroka
2010-07-16, 11:46 AM
There's more of it, yes, which means it's doing much more damage.

Exactly. It's not a matter of hotter, but of more of your surface area being covered by some kind of burning liquid. That would translate to more damage.

And FWIW, the damage caused by fire doesn't seem to correlate in any way to the heat of it, but to the size of the flame (again, surface area if anything).

But even that's all details that D&D is incapable of modelling. Saying dragon flames are hotter than a fireball when (and only when) they deal more damage is just conjecture; fire attacks deal damage based on the source of the attack and its level or CR or HD, in general.

Fouredged Sword
2010-07-16, 11:48 AM
I think you would get more bang for your buck buying wands of acid spells that ignore SR. Mr Melph made some nice spells for takeing out golems. If you can get some 10 to 20 wands of melph's acid arrow into the hands of some adepts or low level wizards or such, then pound the golems into acid covered rubble. If you can, see if your DM will let you make a pre metamagiced wand so you can make them all have reach.

See if you can use multiple mages to speed creation of magic items. I don't know if it's within the rules, but I would at least try to talk your DM into letting you make three shifts of workers to triple your production rate.

Aroka
2010-07-16, 11:51 AM
Speaking entirely RAW?

RAW, it seems it would do 1d6 damage X times.

However, RAW, that's not a problem for you (http://www.d20srd.org/srd/specialAbilities.htm#resistanceToEnergy):
(Emphasis mine)

Outside of RAW, both of those seem odd to me.

Strictly by RAW, there's no rules for larger units of alchemist's fire. Taking X standard actions in X rounds to throw X flasks of the stuff at an enemy, making X attack rolls, would deal 1d6 damage X times... but that's it.

Curmudgeon
2010-07-16, 11:57 AM
Speaking entirely RAW?

RAW, it seems it would do 1d6 damage X times.

However, RAW, that's not a problem for you (http://www.d20srd.org/srd/specialAbilities.htm#resistanceToEnergy):
You're a bit behind on your rules changes. From Rules Compendium on page 48:
RESISTANCE TO ENERGY

A creature that has resistance to energy has the ability (usually extraordinary) to ignore some damage of a certain energy type each time it takes damage of that type. This is yet another change introduced in this "collection of existing rules". Energy resistance works the same as DR: it's subtracted on each occurrence, without per round limits.

DaTedinator
2010-07-16, 09:18 PM
Strictly by RAW, there's no rules for larger units of alchemist's fire. Taking X standard actions in X rounds to throw X flasks of the stuff at an enemy, making X attack rolls, would deal 1d6 damage X times... but that's it.

Haha, touché! I suppose I wasn't speaking entirely RAW.


You're a bit behind on your rules changes. From Rules Compendium on page 48: This is yet another change introduced in this "collection of existing rules". Energy resistance works the same as DR: it's subtracted on each occurrence, without per round limits.

A good change that needed to be made. But yeah, I agree on the silliness of making rules changes in a collection of "existing" rules.